Surgeons, believing this "centrifugal theory"—cancer's stainlike, outward spread from a central mass—advocated ever-widening surgical extirpations to eliminate cancer.
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"We're witnessing complete extirpations at a rate that's pretty remarkable," David Sischo, the snail extinction prevention program coordinator at the Hawaii Department of Land and Natural Resources, said in an interview.
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Marine species may be more vulnerable to extirpations—extinction from a local habitat—in part because they cannot seek refuge from extreme temperatures as easily as land animals, the study suggests.
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"We tested for this effect [and] found that extirpations at the warm edges of species' ranges were twice as common in the ocean (56 percent) as on land (27 percent)," they said.
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Lizards are ectotherms that regulate body temperature using heat sources of their local environment (the sun, warm air temperatures, or warm rocks). Surveys of 200 sites in Mexico showed 24 local extinctions (= extirpations), of Sceloporus lizards. Using a model developed from these observed extinctions the researchers surveyed other extinctions around the world and found that the model predicted those observed extirpations, thus attributing the extirpations around the world to climate warming. These models predict that extinctions of the lizard species around the world will reach 20% by 2080, but up to 40% extinctions in tropical ecosystems where the lizards are closer to their ecophysiological limits than lizards in the temperate zone Huey, R. B., Deutsch, C. A., Tewksbury, J. J., Vitt, L. J., Hertz, P. E., Álvarez Pérez, H. J., & Garland Jr, T. (2009).
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Silvertip sharks are regarded as potentially dangerous to humans, as they often approach divers quite closely. This slow-reproducing species is taken by commercial fisheries for its meat, fins, skin, cartilage, and jaws and teeth, which has apparently led to local population declines or extirpations.
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American marten are trapped for their fur in all but a few states and provinces where they occur. The highest annual take in North America was 272,000 animals in 1820. Trapping is a major source of American marten mortality in some populations and may account for up to 90% of all deaths in some areas. Overharvesting has contributed to local extirpations.
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Sreekar, R., Huang, G., Zhao, J., Pasion, B.O. et al. "The use of species–area relationships to partition the effects of hunting and deforestation on bird extirpations in a fragmented landscape" Diversity and Distributions, Vol. 21. No. 4 (2015). pp. 441-450. . One case study in Panama found an inverse relationship between poaching intensity and abundance for 9 of 11 mammal species studied.
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Logging for West Indian mahogany and buttonwood has also occurred in hammocks along the northern shores of Florida Bay.Craighead 1971. In some cases, habitat loss has been the direct cause of plant extirpations. Although tropical hardwood hammocks tend to be located in patches across the landscape, they compose part of a complex mosaic of communities including mangroves, coastal marshes and prairies, freshwater swamps, and pinelands.
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The ironcolor shiner has a large range in the lowlands of the eastern and central United States but in the western parts of its range there are many disjunct populations and these have suffered declines and extirpations caused by stream siltation and water pollution. It has also declined in the northern parts of its range but the population in New York's Bashakill wetlands is currently stable.
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The northern hogsucker is native to southern Canada and much of the eastern and southern United States. It lives in the rivers of the Mississippi River Basin, its range extending from Oklahoma and Alabama northward to Minnesota. It is present in the Great Lakes and rivers of the mid-Atlantic region. Its current range is similar to its historical distribution, except in western areas, where it has experienced some extirpations.
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Hunters and fishermen will see a movement and decline in species. For example, waterfowl populations will continue to decline as wetlands contract and dry up; and boreal forest species like deer, moose, and elk will decline because of a losses in forest cover. People who fish will see the usual shift northward of species, but also extirpations in southern and central regions of the province. This will be especially prominent in small, shallow habitats (ponds, small lakes, marshes).
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The timing, intensity, level, and duration of management activities must be adapted and monitored (Selby 2007). It has been suggested that proper management practices could play a crucial role in slowing, and possibly even reversing, the current wave of regal fritillary extirpations (Swengel 2004). The Midwest landscape includes few prairie remnants which are embedded in an agricultural matrix (Davis et al. 2007). Thus, it is extremely important that the land surrounding prairie remnants be included in management decisions and practices.
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The species is found in a number of habitats including both tropical rainforest and xeric shrubland, provided enough prey is present to sustain it. The species is listed as Vulnerable by the IUCN, due to the number of regional extirpations, and under Appendix II by CITES, tightly restricting trade in specimens of the animal. Between 2000 and 2010, the total population declined by 30%. In 1994, some 340 giant anteaters died due to wildfires at Emas National Park in Brazil.
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The arrival of the first people about 4,000 years ago and, to a larger extent, of Europeans more than 500 years ago, had a significant effect on Puerto Rico's fauna. Hunting, habitat destruction, and the introduction of non-native species to Puerto Rico led to extinctions and extirpations (local extinctions). Conservation efforts, the most notable being for the Puerto Rican parrot, began in the second half of the 20th century. According to IUCN, as of 2002, there were 21 threatened species in Puerto Rico: two mammals, eight breeding birds, eight reptiles, and three amphibians.
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Trapping, loss or degradation of aquatic habitats through filling of wetlands, and development of coal, oil, gas, tanning, timber, and other industries, resulted in extirpations, or declines, in North American river otter populations in many areas. In 1980, an examination conducted on U.S. river otter populations determined they were extirpated in 11 states, and had experienced drastic lapses in 9 others. The most severe population declines occurred in interior regions where fewer aquatic habitats supported fewer otter populations. Although the distribution became reduced in some regions of southern Canada, the only province-wide extirpation occurred on Prince Edward Island.
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Also some concern on the effects of forest migrations should be evaluated for wildlife because of the possibilities of forest fragmentations and extirpations. It is important to consider that temperature is not the only relevant habitat change factor affected by climate change. Alterations in precipitation patterns, diurnal timing, seasonal intensity, and season length all can reduce the survivorship or reproductive ability of plant species by disrupting phenology and genetic fitness of the population. The ability of plant species to track climate change will be valuable information in predicting the future health, stability, and function of the Earth's forests in the coming decades.
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It has been linked to declines and localised extirpations of several small native fish species. The introduced trout species have had serious negative impacts on a number of upland native fish species including trout cod, Macquarie perch and mountain galaxias species as well as other upland fauna such as the spotted tree frog. The common carp is strongly implicated in the dramatic loss in waterweed, decline of small native fish species and permanently elevated levels of turbidity in the Murray-Darling Basin of south west Australia. Most of Australia's fish species are marine, and 75% live in tropical marine environments.
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The Puerto Rican crested anole has also been introduced to Dominica where it locally is outcompeting the endemic Dominican anole, having already largely displaced the South Caribbean ecotype (traditionally subspecies Anolis o. oculatus), which possibly may require a captive breeding program to ensure its survival. Nevertheless, anoles overall do not appear to have experienced the widespread extinctions and extirpations prevalent among larger Caribbean reptiles. The Culebra Island giant anole is the only anole considered possibly extinct in recent history (other extinct anoles are prehistoric and only known from fossil remains that are millions of years old).
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Nearly all of the world's isolated islands could furnish similar examples of extinctions occurring shortly after the arrival of humans, though most of these islands, such as the Hawaiian Islands, never had terrestrial megafauna, so their extinct fauna were smaller. An analysis of the timing of Holarctic megafaunal extinctions and extirpations over the last 56,000 years has revealed a tendency for such events to cluster within interstadials, periods of abrupt warming, but only when humans were also present. Humans may have impeded processes of migration and recolonization that would otherwise have allowed the megafaunal species to adapt to the climate shift.
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The common crane (Grus grus), also known as the Eurasian crane, is a bird of the family Gruidae, the cranes. A medium-sized species, it is the only crane commonly found in Europe besides the demoiselle crane (Anthropoides virgo). Along with the sandhill (Grus canadensis) and demoiselle cranes and the brolga (Grus rubicunda), it is one of only four crane species not currently classified as threatened with extinction or conservation dependent on the species level. Despite the species' large numbers, local extinctions and extirpations have taken place in part of its range, and an ongoing reintroduction project is underway in the United Kingdom.
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Despite the environmental and social importance of Bladen, threats such as expansion of adjacent agricultural areas, hunting, illegal extraction and development ventures have the potential to severely impact the integrity of the reserve and must be accounted and planned for appropriately. The most pressing threats are currently the advancing illegal xaté palm collectors, known as Xateros, who are causing widespread extirpations of xaté and impacting populations of game species by illegally hunting during xaté palm collecting expeditions. As mentioned above, looting of Mayan archaeological sites is also an important issue. Another major threat comes from poorly planned and unsustainable development particularly from hydroelectric speculators.
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